


Behold, the Dean

by Annie D (scaramouche)



Category: Supernatural
Genre: Alternate Universe - Human, Alternate Universe - Mermaid, Ambiguous/Open Ending, Fantasy, Friendship, Gen
Language: English
Status: Completed
Published: 2010-10-19
Updated: 2010-10-19
Packaged: 2017-10-12 19:01:23
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,902
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/128043
Author URL: https://archiveofourown.org/users/scaramouche/pseuds/Annie%20D
Summary: <blockquote class="userstuff">
              <p>Dean is a merman, Castiel is the scientist studying him.</p>
            </blockquote>





	Behold, the Dean

**Author's Note:**

> Written for a [Dean/Castiel AU kink meme](http://sansdatelimite.livejournal.com/50587.html?format=light&thread=322715#t322715) on livejournal.

Castiel knows from experience that there’s approximately six minutes between Balthazar announcing over the PA system, _“Zachariah is on deck. I repeat, Zachariah is on deck”_ and Zachariah actually walking through his doors.

Castiel uses these six minutes to tidy up his notes, pull on his labcoat, turn on the computer that goes _beep_ impressively, and throw away all evidence of the food he’s been sneaking in.

“Ah, and here’s our pride and joy,” Zachariah booms as he sweeps through the lab doors. Uriel follows just behind him, looking just as unimpressed as he always does.

“Castiel,” Uriel says politely.

Castiel nods an acknowledgement. “Uriel.”

“How is our star player today?” Zachariah walks up to the tank and taps the glass. “How – are – you – to – day?”

“Please don’t do that,” Castiel says, dropping his hands into his pockets so they won’t see them clench into fists. “Slow-talking isn’t going to magically make him understand a language.”

“You don’t have kids, do you?” Zachariah says, clucking his tongue sympathetically. “Of course you don’t, because if you did, you wouldn’t be the only staff member on board who’s never requested a day’s leave during your tenure, but I guess them’s the breaks when you don’t have a life.”

Castiel doesn’t even blink at that. “Is there a reason you’re here? I was going to get some measurements on Dean’s musculature.”

“Dean, Dean, Dean. Why do you insist on calling it that?” Zachariah asks, glancing at the creature sitting at the bottom of the tank. Dean flares his neck fins in response – an equivalent of sticking out his tongue or flipping the bird, not that Zachariah would know.

“Fine,” Castiel says. “I was going to get some measurements on _Subject 103A’s_ musculature.”

“You’re getting attached to it,” Uriel warns darkly. He wraps his knuckles against the glass, the reverberations making Dean narrow his eyes and hiss. Uriel snorts. “It’s nothing but a seamonkey. It’d do you good to remember that, Castiel.”

“See, this is what happens when one gets cooped up too long with no company besides an overweight fish.” Zachariah taps the glass again. “ _Fish!_ ”

Dean flicks his tail, dark green eyes inscrutable.

“Don’t forget, Michael will be flying over from the mainland in a few days, we’re going to discuss Subject 103A’s future,” Zachariah says.

“Yay, Powerpoint,” Uriel says.

“I’ll be ready, sir,” Castiel says. He tolerates Zachariah’s patting his shoulder and Uriel’s suspicious side eye, waiting until the doors are closed and their footsteps gone before he exhales in relief.

Dean’s expression softens and he glides across the tank floor towards Castiel, the movement every bit as elegant and captivating to the eye as the first time Castiel had the privilege of seeing it. Much like everything above his waistline, Dean’s hands are human-shaped, and he taps his knuckles against the glass the way Zachariah did, rolling his eyes.

“I know he’s annoying, but he’s still my boss,” Castiel says, pulling off the stifling labcoat and tossing it aside. “I answer to him.”

Dean raises an unimpressed eyebrow, proving that he understands more than just the vocal language he’s spent the past few months picking up. He pushes himself off the floor, powerful tail propelling him to the top of the tank. His large, webbed hands grip the edge of the glass, just below where the cage extends over the top and keeps him trapped.

“Son of bitches,” Dean says, pointing a fin towards the door.

“Dean,” Castiel says reproachfully. “That’s a very rude term, and you shouldn’t be saying it. Where did you even learn it?”

Dean points at the slightly damp book that’s been tucked between two bars of the cage. Castiel starts; he’d forgotten to hide it during his clean-up, so it’s extremely lucky Zachariah and Uriel hadn’t spotted it. He’s already on thin ice as it is, no need to make things work by letting them know just how many gifts Castiel has been bringing down for Dean.

“Pieeeee,” Dean says, nudging his forehead against the edge of the cage. “Casssss.”

“You’re going to ruin your appetite,” Castiel says, but he fetches the contraband pie anyway.

 

* * *

  
Castiel knew it was going to come down to this. Oh, he’d _hoped_ it wouldn’t, and spent the past couple of weeks being as deep in denial as possible about it while cherishing his time with Dean, but as with all things, it’s finally come down to the bottom line, and the bottom line is Michael.

“We’ve got to cut him up,” Michael says. In the tank behind him, Dean stiffens. No one notices except Castiel, of course, because no one notices Dean beyond what’s convenient for them.

“Of course, I agree,” Zachariah says immediately, because he’s a sycophant and an idiot. “They’re so much easier to study when they aren’t wriggling around.”

“But then he’ll stop,” Castiel says. Uriel and Zachariah turn twin glares on him, but Castiel pushes on. “He won’t grow or react or evolve. He’ll just be tissue and bone, static and unchanging.”

“We’ll still learn a hell of a lot more than what we’re learning right now,” Michael says, waving Castiel off. “You were allowed to bring him out here because of your theory that he’s part of a pack, but there’s been nothing on the sonar. We’ve given you the four weeks you wanted, and now your time’s up. Either you put him down or I’ll bring someone who will.”

Castiel steals a quick look at Dean, whose long, serpentine tail is swishing dangerously, fins flaring at every breath in and out. Dean slowly lifts his gaze to meet Castiel’s, his eye full of questions and hope and fear that only Castiel can read.

“I...” Castiel has to look away. “Please give me time to think about this.”

“Sure, sure,” Michael says easily, because of course, it’s no problem for him. Uriel touches Castiel’s shoulder in a surprising show of kindness before leaving with their bosses, and then it’s Castiel and Dean alone again in the lab, perhaps for the last time.

“Dean...” Castiel says, turning to the tank.

Dean’s already at the surface, hands wrapped around cage bars and shaking them. “Want home, Casssss. Want out.”

“I know,” Castiel says, quickly climbing up the ladder alongside the tank so they can be eye-to-eye. He usually loves it up here, where he’s able to converse with Dean and appreciate all his facial expressions up close, but now it’s torture, Dean’s pain and fear so palpable. “I’m sorry, Dean, but I’m just one person and the ship is full of people who answer to Michael. What do you expect me to do?”

“Cas...” Dean’s mouth curls unhappily, eyes flashing angry green. “You, me? We done.”

Castiel exhales shakily. “Dean—”

Dean slams his hands against the glass. “We _done_!” He submerges with a loud splash, slinking down to the bottom of the tank and covering his head with his tail.

 

* * *

 

  
It doesn’t take that long for Castiel to realize that despite his fears, there’s no way he’ll allow Dean to die, whether by his hand or anyone else’s. He may have been a good employee for decades, loyal to a fault and having willingly signed miles of non-disclosure agreements (in blood, it often seems like), but everyone has lines that they will not cross, and Castiel has found his.

Decision made, Castiel runs on adrenaline, mapping out the shortest escape route through the ship, hacking the computer systems to dismantle the security features in his way, and calculating the best window of time to move.

When he returns to the lab, Dean is asleep, curled tightly in a corner of the tank. Castiel knocks the glass, which makes Dean snap awake, irritated and glaring until he sees Castiel put a finger to his mouth and point upwards.

Dean makes a crooning sound when Castiel unlocks the cage, garbling happily as he hoists himself over the edge of the tank.

“I’m going to have to carry you,” Castiel says apologetically. “I couldn’t figure out any other practical way to transport you to the upper deck.”

Dean looks at Castiel, then at himself. “Not a girl,” he says with a scowl.

“I know that, Dean,” Castiel says. It takes some maneuvering and adjusting of weight, but soon enough Dean is draped on Castiel’s back, arms around Castiel’s neck (careful not to choke him) and tail flapping restlessly against the floor. Dean can take some of his own body weight when they’re still, but once they start, Castiel’s going to have to keep moving until they get there or his back goes out.

“Very warm, Cassss,” Dean says, sounding surprised. He nuzzles behind Castiel’s ear, the sensation of Dean’s nose against Castiel’s skin strange, wet and very ticklish.

“Time to go, Dean,” Castiel says, suppressing laughter, and they’re off.

They make it as far as the lower deck before they’re finally spotted. There aren’t that many security guards on board since the ship technically doesn’t exist at all, but what few they have are highly paid and highly motivated.

“Shit,” Dean says when the alarms go off around them.

“Almost there!” Castiel rushes towards the doors that head out to the stern. “Open the door for me!”

Dean slams his tail against the door, full strength almost splintering the wood. Castiel’s back is killing him but they’re out in the open, Dean already making noises at finally smelling sea air again.

A security guard slams into them as they’re making the final dash. Castiel fights with what strength he has, kicking and punching and biting anything he can reach, eventually hitting the guard with a bucket and putting him out. Castiel grabs his gun while Dean crawls towards the edge of the ship, the space at the bottom of the railings just wide enough for Dean to squeeze through.

“Casssss?” Dean calls out, trying to fold his tail to fit between the railing.

“I’m here, Dean,” Castiel says, rushing to his side and helping press Dean’s fins down so he can slide through. Behind them he can hear people shouting and the sound of feet running; they don’t have much time.

“Sam?” Dean says, peering over the edge of the ship at the sea below. He makes a high-pitched sound. “Sam!”

“Go, Dean, go,” Castiel says urgently. The gun is an unfamiliar weight in his hand, but he turns back around and holds himself steady. “Go to your brother.”

“Cas?” Dean grabs Castiel’s arm. “Come with.”

“No, Dean,” Castiel says. “You have to swim as fast as you can, or they’ll catch you again and this’ll all be for nothing. I’ll hold them off for you. I’ll hold them all off.”

Dean shakes his head, pulling insistently at Castiel’s arm. “Cassss—”

“I said go!” Castiel wrenches his arm away and shoves Dean overboard. Dean makes a squawking sound that’s followed up by a blessed splash of water. Castiel can almost make out two voices in the shrill, dolphin-like noises that follow, Dean and his brother reunited at long last.

Castiel takes a deep breath, keeping the gun close to his body, and runs. He won’t be able to make it to the engine room, but he can find a computer console and make it more difficult for them to find Dean.

Raphael catches up with him just as he's killing the navigation systems.

Castiel closes his eyes. It's all worth it.

**Author's Note:**

> auto-floss over on LJ has written a [happy ending coda](http://auto-floss.livejournal.com/82544.html)!
> 
> This fic has [accompanying artwork!](http://made-of-tin.livejournal.com/4808.html)


End file.
